Pumping-engine.



B. 0. GAGE. PUMPING ENGINE.

APPLICATION FILED DEG. 16, I908.

Patentd Oct. 11,1910.

2 SHEETSSHEET 1.

B. O. GAGE.

PUMPING ENGINE.

APPLICATION FILED DEO.'16, 1900 w 1 a 1 o a .m 0 l O m m Q 1 M O f l 8 wa 1 Q u o o o 0 0 m. Q Q

UNITED STATES PATENT OFFICE.

BURT O. GAGE, OF WARREN, MASSACHUSETTS, ASSIGNOR TO WARREN STEAM PUMPCOMPANY, A CORPORATION OF MASSACHUSETTS.

PUMPING-ENGINE.

Specification of Letters Patent.

Patented Oct. 11, 1910.

Application filed December 16, 1908. Serial N 0. 467,883.

To all whom "it may concern:

Be it known that I, BURT O. GAGE, a citi- Zen of the United States,residing in Warren, in the county of Worcester and State ofMassachusetts, have invented an Improvement in Pumping-Engines, of whichthe following description, in connection with the accompanying drawings,is a specification, like letters on the drawings representing likeparts.

This invention relates to a pumping engine, and especially to the pumpproper of a double acting, independent air pump for use in connectionwith condensing steam engines.

The peculiar nature of the operation of an air pump for discharging thecontents of a condenser of a steam engine and maintaining a high vacuumtherein is such as to call for special construction of the pump proper,and it has been found, heretofore, that for an independent air pump,especially of the twin type, a single acting bucket pump is mosteffective, and such construction has been most commonly adopted forindependenttwin air pumps.

I have devised a double-acting piston pump capable of producing andmaintaining a high vacuum, and being more compact and economical ofspace than the bucket pumps heretofore commonly used, and having theadvantages of easy maintenance and ready accessibility 'of parts forrepair or replacement, when required.

Figure l is a front elevation of a double acting twin air pump embodyingthis invention, one of the pumps being shown partly in section; Fig. 2is a sectional plan thereof on line 011 Fig. l; and Fig. 3 is avertical, longitudinal section through one of the pumps on line a ofFig. 2.

The invention is shown embodied in a twin pumping engine, and thegeneral arrangement is the same as in twin air pumps heretofore used,the engine comprising a pair of pumps 2, 3 (see Fig. 1) having suctionand discharge chambers common to both, and connected by uprights 1 witha base plate 5 for the actuating engine or steam cylinders 6, 7,corresponding to, and in line with the pump cylinders, the pistons ofthe steam cylinders being each connected by a piston rod 8 with thepiston of the corresponding pump, so that each steam cylinder and pistonwith the corresponding pump constitutes a direct acting pumping engine.The piston rods of the two pumping engines are connected by a rockingbeam 9 which causes the pumps to operate in unison, but to make theirstrokes in op osite directions, the power of both steam cylinders thusbeing exerted in each stroke, and transmitted to the pump pistons inaccordance with the load on each, at any given stroke or time in thestroke.

The organization thus far considered, except for the construction of thepumps, which will be hereinafter described, and the fact that pistons,instead of buckets or valved pistons, are used in the pumps proper, issubstantially the same as has been heretofore used in independent twinair pumps, and the construction of the steam cylinders and theirappurtenances, including the valve mechanism, may be of any suitable orusual construction, and, if desired, a single steam cylinder might beused connected directly to the piston of one of the pumps, and throughthe rocking beam 9 to the piston rod of the other pump, so as to operatethe pump pistons in unison but in opposite directions, the same as whentwo steam cylinders are employed.

The structure of the pump comprises four principal components, viz., thebase portion 10 containing the suction chamber common to both pumps, andthe two cylinder pieces or sections 11, 12, and the discharge chamber13, common to both cylinders, and mounted upon the cylinder pieces 11,12, and constituting the direct support for the frame work of theactuating cylinders or steam end of the pump.

The construction of the individual pumps is best shown in Fig. 3. Thebase 10 contains the suction chamber 14., provided with a suitable inletpassage, as indicated at 140, Figs. 2 and 3 (being structurally similarto the outlet passage 27 shown in Fig. 1, but at the rear of the pump),said suction chamberbeing of annular form where it is adjacent to theend of the cylinder proper, the base portion 10 containing a recess 15within the suction chamber 14, corresponding in position to the cylinderproper 16 and of larger diameter or sectional area, so as to afford aspace between the wall of the cylinder proper and the inner wall of thesuction chamber 14:, as shown at 17 Figs. 2 and 3, the lower end of thecylinder proper 16 extending down into the recess 15 in the baseportion, and having its lower end a substantial distance below the levelof the top of the suction chamber 14;.

Each cylinder piece contains the cylinder proper 16and a surroundingwall or casing extending to the outer wall of the suction chamber let,and having a space between it and the cylinder proper divided by a vertical partition 18, as best shown in Fig. 2, thus forming two separateintermediate chambers 19, 20, which together surround the cylinder16,above the base casting and suction chamber, which latter communicateswith both of the said intermediate chambers through openingscontrolledby upwardly opening valves 21 which may be such as commonly employedbetween the suction chamber and cylinder or barrel of a pump.

The cylinder piece is provided with a flange 22 extending. around oneside of the cylinder 16, from one to the other of the partitions 18,which flange seats upon the base piece above the inner wall of thesuction chamber 1 1, as shown at the left hand in Fig. 3,'and thus cutsoff communication between the intermediate chamber 19 at that side ofthe vertical partitions 18 and the chamber 15 communicating with thelower open end of the cylinder proper 16, while the intermediate chamber20 at the other side of said partitions 18 is in free communicationthrough the space 17 (see Figs. 2 and 3) with the recess 15 in the basepiece and with the lower end of the cylinder 16 which opens directlyinto said recess.

The wall of the cylinder proper 16 is extended at one side of thevertical partitions 18 to the top of the cylinder piece, thus cuttingoff communication between the intermediate chamber 20 and the upper endof the cylinder, as is clearly shown in Fig. 3, while at the other sideof the said partition 18, the cylinder wall terminates a little belowthe upper end of the cylinder chamber, thus leaving a passage or space23 which affords communication between the intermediate chamber 19 andthe upper end of the cylinder. The piston 24 may be of any suitable orusual construction, and by reason of the construction thus fardescribed, it will be seen that the cylinder 16'communicates at itslower end only with the intermediate chamber 20, and at its upper endonly withthe intermediate chamber 19, and

' that the upper end of the cylinder communicates with the upper end ofthe intermediate chamber 19 near the top wall of said chamber, and thelower end of the cylinder communicates through the passage 17 with theintermediate chamber 20 at the bottom of the latter.

The discharge chamber 25 in the top section of the pump portion of theengine overlies both of the cylinder pieces 11 and 12 substantially tothe outer wall, and thus lies above both intermediate chambers 19, 20 ofboth pumps, and communicates with said intermediate chambers throughopenings controlled by upwardly opening valves 26 which are opened topermit the flow of fluid from the intermediate chambers into thedischarge chamber to prevent the reverse movement of the fluid, as isusual in pumps. The top section 13 is provided with a suitable dischargeoutlet 27 common to both pumps, as best shown in Fig. 1.

The upper section 13 has openings completely through it above thecylinders, each opening receiving the corresponding cylinder head 28which is made cup-shaped, as best shown in Fig. 3, sons to afford acuplike or open top chamber or recess above the piston head, andsurrounded by the discharge chamber, which recess in the cylinder headreceives any liquid which may leak through the stuffing box so that thesaid liquid tends to prevent the passage of air or vapor through thestuffing box.

The outer wall of the cylinder sections 11 and 12 is contracted towardthe cylinders 16 contained therein in the space between the suction anddischarge chambers, as shown at 30, which reduces the capacity of theintermediate chambers 19 and 20, and gives comparatively small clearancespace between the piston and the inlet and outlet valves.

Hand holes with removable covers are provided in the cylinder pieces andin the top and base sections, as shown at 32, 33, 341', Fig. 1, foraffording access to the valves which may thus be repaired or replaced,without having to obtain access to the interior of the cylinder, as isthe case with reference to the valves in the bucket of a single actingbucket pump.

While the invention has been herein shown and described as embodied in atwin pump or pair of pumping engines connected for simultaneous andequalized operation by a rocking beam, the invention, so far as itrelates to the novel construction of the pump cylinder and partsdirectly cooperating therewith, is embodied in a single one of the pumpsand cooperating parts, and Fig. 3, for example, may be understood asrepresenting the pump end of a complete pump embodying the invention, itbeing understood that there is a suitable inlet to the suction chamber11 and outlet from the discharge chamber 25, whether the cylinder worksalone or in combination with the other cylinder of a twin pump.

By reason of the nature of the material being pumped, part being liquid,and part being vapor or gaseous, the operation is somewhat different atthe two ends of the cylinder, and the operation of the parts incommunication with the lower end of the cylinder during a stroke is asfollows: When the piston has completed its down stroke which extendsclear to the bottom of the cylinder 16, under usual conditions when thepump is in continuous operation, the gaseous material and a part of theliquid will have been expelled through the discharge valves 26 and theintermediate chamber 20 which is in communication with the lower end ofthe cylinder, as well as the space 15 below the cylinder, and theconnecting passage 17 Wlll be full of liquid. \Vhen the piston makes itsupstroke, the liquid will follow it through the open, lower end of thecylinder, and will descend in the intermediate chamber 20, the liquidfollowing the piston from the intermediate chamber into the cylinder.During or toward the latter part of the upstroke of the piston, thepressure in the intermediate chamber will have been so reduced that theslight pressure in the suction, chamber 1 1 is sufiicient to open thevalves 21, and the air and vapor from the suction chamber will passthrough the said valves into the intermediate chamber 20, and if liquidbegins to pass before the liquid in the chamber has been drawn down tothe level of the lower end of the cylinder, no air will pass into thecylinder, but the air and vapor will accumulate in the intermediatecham-* ber 20 above the level of the liquid therein. In the down strokeof the piston, the liquid will be forced from the cylinder through thepassage 17 into the intermediate chamber 20, and rising therein willexpel the air and vapor through the discharge valves 26, and finally ifthere is more than enough liquid to fill the intermediate chamber orclearance space between the piston and the discharge valves 26, someliquid will be discharged through the said valves 26, leaving the saidclearance space entirely filled with liquid at the end of the stroke.Thus, in the usual operation, the level of the liquid outside thecylinder will not at any time descend below the level of the lower endof the cylinder, and the vapor will not enter the cylinder, so that thepiston, for the most part, acts directly against liquid rather thangaseous material. If, however, the liquid in the intermediate chamber,together with that entering the same in the upstroke of the piston isinsuiiicient completely to fill the lower part of the cylinder, itslevel outside the cylinder would descend, and when it arrived at thelower end of the cylinder, the gaseous material would pass into thecylinder and accumulate between the piston and the column of liquidtherein. In the next down stroke of the piston, however, the gaseousmaterial would be entirely expelled from the cylinder, and rising to thetop of the chamber would pass out through the discharge valves 26, orremain above the liquid in the intermediate chamber 20, and at the nextupstroke the piston would be followed by the liquid material enteringthe cylinder, as previously described. In the case of the otherintermediate chamber 19 which communicates with the upper end of thecylinder, the said chamber will, in the usual operation, remain filledwith liquid at all times up to the level of the upper end of thecylinder. \Vhen the piston has completed its upstroke, the slight spaceabove it and the intermediate chamber 19 communicating with it willusually be filled with liquid up to the level of the valve 26 throughwhich some of the liquid has been discharged after the gaseous materialhas been discharged. hen the piston makes its down stroke, the liquidabove the level of the top of the cylinder will lie upon the piston andtravel down with it in creating the vacuum in the upper part of thecylinder, and in the slight space above the level of the upper endthereof, until the pressure is sufliciently reduced to cause thepressure in the suction chamber 14 to open the valves 21 when the vaporor gaseous material will first pass up through the liquid from thechamber 19 into the space in and above the cylinder above the piston.hen more liquid follows through the suction valves 21 from the suctionchamber it will flow over the upper edge of the cylinder and down intothe cylinder upon the liquid already resting on the piston therein.lVhen the piston makes its upstroke, it will first discharge all thegaseous material through the discharge valves 26, and thereafter if theliquid contents are greater than the clearance space, will dischargeliquid through the discharge valve 26, the entire space between thesuction and discharge valves being full of liquid at the end of thestroke in the usual operation.

It sometimes happens, especially in starting the pump, that sufficientliquid does not enter or accumulate'in one of the chambers, and, at thesuction stroke of the piston, the rarefaction of the air by expansionfrom the intermediate chamber into the cylinder does not reduce thepressure to that in the suction chamber, or enough below it to cause thevalves 21 to be lifted, and in such event the air would merely becompressed to about atmospheric pressure at the next forcing stroke, andagainexpanded at the next suction stroke of the piston, without causingany draft from the suction chamber. In such event, others of theintermediate chambers will have become wholly or partially filled withthe liquid as the operation continues, and the equalizing connectingduct 35 will permit some of the liquid to flow from the chambersrelative to which the piston is making its forcing stroke to the chamberrelative to which the piston is making its suction stroke, so that theliquid will enter the latter and thus reduce the clearance space for thegaseous material, so that on the suction stroke it will be sufficientlyrarefied to cause the suction valves to open and the pumping action togo on properly. This equalizing, connecting passage or duct should be ofrelatively small capacity, and when all of the chambers containsufficient liquid to insure the proper working, the flow through saidequalizing duct will be very slight, and may, if desired, be entirelyshut off by valves provided for that purpose, as shown at 36.

As the piston operates to discharge the fluid at both strokes, it may bemade of half the sectional area required for the bucket piston of asingle acting pump of otherwise equal dimensions, and the setting of thecylinder so that its lower end is well below the upper part of thesuction chamber permits the height of the pump portion or pump end ofthe pumping engine to be correspondingly reduced, so that a relativelycompact structure is produced, which is an extremely desirable featurefor pumps of this character, which are frequently used where thegreatest economy of space is a requisite. The reduction of the sectionalarea of the piston thus made possible by utilizing its complete pumpingaction, (suction and discharge) at both strokes, admits of the pistonitself, and the piston rod and moving parts associated therewith, beingmade much lighter than in a single acting pump of equal speed in strokesper minute, and of equal capacity, which lightening of the moving partsaffords a substantial advantage inconstruction and operation, as themomentum of heavy moving parts is objectionable in the operation ofpumps of this character.

' The construction and arrangement of the pump cylinder, suction anddischarge chambers, and intermediate chambers, are such that the valvecontrolled openings, through which the fluid is discharged, are at thehighest point relative to the space from which the fluid is discharged,so that no air or gaseous material is trapped at any pointand,furthermore, the construction is such that, in the continuous regularoperation, the piston is at all times in direct contact with the liquid,and there is always a complete separation of the liquid and gaseouscontents, with the gaseous portion when present always in the. upperpart of the intermediate chambers and adjacent to the discharge valves,so that if there is liquid enough to fill the clearance space, thegaseous material will be entirely expelled at each forcing stroke of thepiston. The fact that the piston works in contact with the liquidcontents tends to prevent or reduce leakage past it, and that factcoupled with the relatively small piston area and momentum of the movingparts, reduces the obj ectionable shock such as is experienced when abucket or plunger or piston makes the first part of its stroke in thegaseous material, and encounters the surface of the liquid below thegaseous material when said piston is at mid-stroke and in rapidmovement, so that a violent blow is struck upon the surface of theliquid.

In the present construction, there is no impact or blow struck by thepiston against the liquid, even when the amount of liquid in theclearance space is insufiicient to fill the cylinder. In that event,gaseous material will enter the cylinder at its lower end, and will liebetween the piston and the liquid when the piston has arrived at the endof its upstroke, but, in the next down stroke, the gaseous materialbetween the piston and the liquid will force the liquid downward out ofthe cylinder in advance of the piston, and

a will then itself be discharged from the lower end of the cylinder, andwill rise through the liquid in the intermediate chamber and be expelledthrough the discharge valve, and the piston will encounter the surfaceof the liquid only at the moment when the piston is practically at theend of its downward stroke, so that no appreciable impact will beexperienced.

I claim:

1. A pumping engine comprising, in combination with an actuatingcylinder and piston, a pump cylinder and )iston; and a base for saidpump cylinder, having a suction chamber surrounding the lower end ofsaid cylinder, and forming therewith a recess surrounded by and normallycut off from said suction chamber and communicating with the lower endof said cylinder; and separate intermediate chambers one communicatingwith the lower end only, and the other with the upper end only of saidpump cylinder; and a discharge chamber above said intermediate chambers;and valves controlling communication between the suction chamber andintermediate chambers, and located substantially at the junction of saidchambers and said recess, and valves controlling communication betweenthe intermediate chambers and discharge chamber, substantially asdescribed.

2. A pumping engine comprising, in combination with an actuatingcylinder and piston, a pump cylinder and piston; and a base for saidpump cylinder, having a suction chamber surrounding the lower end ofsaid cylinder, and forming therewith a recess surrounded by and normallycut off from said suction chamber and communicating with the lower endof said cylinder; and separate intermediate chambers one communicatingwith the lower end only, and the other with the upper end only of saidpump cylinder; and a discharge chamber .above said intermediatechambers; and

valves controlling communication between the suction chamber andintermediate chambers, and located substantially at the junction of saidchambers and said recess, and valves controlling communication betweenthe intermediate chambers and discharge chamber, said pump cylinderhaving its lower end open in said recess of the base below the level ofthe top of the suction chamber, substantially as described.

3. A pumping engine comprising, in com bination with. an actuatingcylinder and piston, a pump cylinder and piston; and a base for saidpump cylinder, having a suction chamber surrounding the lower end ofsaid cylinder, and forming therewith a re cess surrounded by andnormally cut off from said suction chamber and communicating with thelower end of said cylinder; and separate intermediate chambers onecommunicating with the lower end only, and the other with the upper endonly of said pump cylinder; and a discharge cham ber above saidintermediate chambers, and valves controlling communication between thesuction chamber and intermediate chambers, and located substantially atthe junction of said chambers and said recess, and valves controllingcommunication between the intermediate chambers and discharge chamber,said intermediate chambers surrounding the pump cylinder and havingtheir outer walls contracted toward the pump cylinder which constitutesthe inner wall thereof, substantially as and for the purpose described.

4. A pumping engine comprising, in combination with an actuatingcylinder and piston, a pump cylinder and piston; and a base for saidpump cylinder, having a suction chamber surrounding the lower end ofsaid cylinder, and forming therewith a recess surrounded by and normallycut off from said suction chamber and communicating with the lower endof said cylinder; and separate intermediate chambers one communicatingwith the lower end only, and the other with the upper end only of saidpump cylinder; and a discharge chamber above said intermediate chambers;valves controlling communication between the suction chamber andintermediate chambers, and located substantially at the junction of saidchambers and said recess, and valves controlling communication betweenthe intermediate chambers and discharge chamber; and a cup-like cylinderhead, closing the upper end of the cylinder and surrounded by thedischarge chamber, substantially as described.

5. A pumping engine comprising, in combination with an actuatingcylinder and piston, a pump cylinder and piston; and a base for saidpump cylinder, having a suction chamber surrounding the lower end ofsaid cylinder, and forming therewith a recess surrounded by and normallycut off from said suction chamber and communicating with the lower endof said cylinder; and separate intermediate chambers one communicatingwith the lower end only, and the other with the upper end only of saidpump cylinder; and a discharge chamber above said intermediate chambers;valves controlling communication between the suction chamber andintermediate chambers, and located substantially at the junction of saidchambers and said recess, and valvds controlling communication betweenthe intermediate chambers and discharge chamber; and an equalizing ductaffording communication between said intermediate chambers,substantially as and for the purpose described.

6. A twin pumping engine, comprising, in combination, two pump cylindersand pistons and piston rods connected therewith, and a rocking beamconnecting said piston rods for simultaneous operation in oppositedirections; a steam cylinder and piston connected with one of said rods;a base having a suction chamber common to both pump cylinders, andseparate intermediate chambers cooperating with each cylinder, onecommunicating with the lower end only, and the other with the upper endonly of said cylinder; a discharge chamber common to both pump cylinderslocated above the intermediate chambers; and valves in the upper wall ofthe suction chamber around the 100 cylinder, controlling communicationbetween the suction chamber and intermediate chambers, and valves at theupper ends of the intermediate chambers around the cylinder head,controllin, communication between the 105 intermediate chambers and thedischarge chamber, substantially as described. v

7. A twin pumping engine, comprising, in combination, two pump'cylinders and pistons and piston rods connected therewith, 110 and arocking beam connecting said piston rods for simultaneous operation inopposite direct-ions; a steam cylinder and piston connected with one ofsaid rods; a base having a suction chamber common to both pump 115cylinders and surrounding the same to form recesses between said suctionchamber and the lower ends of said cylinders, and separate intermediatechambers cooperating with each cylinder, one communicating with the 120lower end only, and the other with the upper end only of said cylinder;a discharge chamber common to both pump cylinders; automatic valv'escontrolling communication between the suction chamber and intermedi- 12ate chambers and located substantially at the junction of said chambersand said recess, and automatic valves controlling communication betweenthe intermediate chambers and discharge chamber; and an equalizing 1duct aflording communication between all of said, intermediate chambers,substantially as and for the purpose described.

' suctionichamber, and having at its upper end an annular dischargechamber, a cylinder located in said casing and extended from near thedischarge chamber into said well to form with the inner wall of thesuction chamber an annular space or recess about the lower'end of saidcylinder, means extended longitudinally of the cylinder to separate thespace between the cylinder and the easing between the suction anddischarge chambers into intermediate chambers, means to out 01f one ofsaid intermediate chambers from said well, automatic valves for saidsuction and discharge chambers, the automatic valve for said suctionchamber being located substantially on a level with the junction'of thesaid recess with one of said intermediate chambers and a piston in saidcylinder of the internal diameter of the latter, substantially asdescribed.

9. In a pump of the class described, in combination, a cylinder open atits upper and lower ends, a piston therein, a casing surrounding saidcylinder and provided with means for reducing the width of the spacebetween the cylinder and casing between the top and bottom of thelatter, a suction chamber communicating with said space below thereduced portion and surrounding the lower end of said cylinder to formtherewith a recess, a discharge chamber communicating with the saidspace above the reduced portion, automatic valves located substantiallyon a level with the junction of said recess with one of the intermediatechambers and controlling communication between said suction chamber andsaid intermediate chamber, automatic valves cont-rolling communicationbetween the intermediate chambers and the discharge chamber, means forseparating said space into chambers between said suction and dischargechambers, and means for cutting off one of said intermediate chambersfrom the lower end of said cylinder,substantially as described.

10. In a pump of the class described, in combination, a cylinder open atits upper and lower ends, a piston therein, a casing surrounding saidcylinder, a suction chamber within said casing whose inner wall ,forms awell normally cut ofl from said suction chamber and within which thelower end of the cylinder is extended to form a recess about saidcylinder, said suction chamber having a fluid inlet, and a fluid outletin close proximity to the upper end of said fluid inlet andsubstantially on a level with the upper end'of said recess, an automaticvalve controlling said fluid outlet, a discharge chamber communicatingwith the casing above the open upper end of said cylinder, and providedwith a fluid inlet from said casing, an automatic valve controlling thefluid inlet for said discharge chamber, means extended longitudinally ofsaid cylinder between said suction chamber and said discharge chamber toform intermediate chambers with one of which only the upper end of thecylinder communicates near the bottom of the discharge chamber, and withthe other of which only the lower end of the cylinder communicates nearthe bottom of sald intermediate chamber, and means to cut off said wellfrom the intermediate chamber with which the upper end of the cylindercommunicates, substantially as described.

11. In a pump of the class described, in combination, a cylinder open atits upper and lower ends, a piston therein, a casing surrounding saidcylinder, a suction chamber within said casing whose inner wall forms awell which is normally cut off from said suction chamber and into whichthe lower end of said cylinder is extended to form a recess about saidcylinder, a discharge chamber within said casing, located above thecylinder in proximity to its upper end, means for separating the spacebetween the said cylinder and easing into intermediate chambers, meansto cut off one of said chambers from the said well and leave the otherof said chambers in open communication with said well at the bottom ofthe said intermediate chamber, automatic valves located substantially ona level with the junction of said chambers and said recess, andautomatic valves controlling communication between said intermediatechambers and said discharge chamber, substantially as described.

12. In a pump of the class described, in combination, a cylinder open atits upper and lower ends, a piston therein, a casing surrounding saidcylinder and provided at its lower end with a suction chamber having afluid inlet in the casing and provided with an annular inner wall withinthe casing forming a well and an annular upper wall located in closeproximity to the upper part of the said fluid inlet, the lower end ofsaid cylinder being extended into said well to form an annular space orrecess between the cylinder and the inner wall of said suction chamber,an annular discharge chamber supported by said casing above the upperend of the said cylinder, automatic valves located in the upper wall ofsaid suction chamber and the bottom wall of said discharge chambersubstantially on a level with the upper end of said recess, means toseparate the space between said suction and discharge chambers intointermediate chambers, one of which is in open communication at itsbottom With said Well by said annular space, means cooperating With saidcylinder and the inner Wall of said suction chamber to close a portionof said annular space and thereby cut ofl the other of the intermediatechambers from said Well, means to restrict the diameter of theintermediate chambers between said suction and discharge cham- 10 bersand means for connecting one interme- 'tWo subscribing witnesses.

BURT O. GAGE.

WVitnesses Jos. P. LIVERMORE, M. E. CovENEY.

